Just an update. My server has been running perfectly for over a year. I now have a 3TB WD Red as the parity drive, a 300GB 7.2k RPM for cache, then for data a 2TB WD Red, and a random 1TB and 500GB I had laying around. So, 3.5TB of usable storage space at the time, with room to add more when needed. Will probably buy another 3TB WD Red in the near future.
I've updated the code regularly when Tom puts out updates. So I'm fully up to to date.
I was running unmenu, but got rid of it because I didn't feel I needed it. I was also running simplefeatures UI, but removed that to instead use Tom's new GUI. I prefer to keep everything stock if possible.
Thanks to all for the advice in this thread and others along the way. I still read/lurk here a few times a week, and enjoy reading the discussions.